More Solar Panel Problems For ISS

rufey writes "This week there have been two pieces of bad news from the International Space Station. First was the discovery of metal shavings inside a problematic rotary joint used to keep one set of solar panels in the optimal position for power generation. At the close of a subsequent spacewalk, after it was relocated to its permanent location, the unfurling of the 4B solar panel resulted in it tearing in two places. A spacewalk is now planned for November 4th to attempt to fix the tear. The upcoming spacewalk is not without risks, including the remote possibility of electrocution since it is impossible to stop the solar panel from generating electricity during the repair attempt. NASA says the ripped wing needs to be fixed or the solar rotary joint problem solved before any more shuttles can fly to the space station and continue construction. With a hard deadline of 2010 for Shuttle retirement, NASA does not have much wiggle room in the schedule in order to finish ISS construction."

Comments

Impossible to stop the solar panel from generating

[Anonymous Coward]

Why don't they do the repairs at night?

Deadline

[ktappe]

Why is 2010 such a "hard" deadline? Was it not created solely by politicians who wanted to divert resources to go to Mars? As such, can it not be moved just as easily as it was created? It is, after all, three years away. If we can't move deadlines that far out, isn't there a chance we're overplanning, and leaving ourselves completely vulnerable to unexpected circumstances, exactly like this solar panel issue?

Re:Deadline

[DerekLyons]

Why is 2010 such a "hard" deadline? Was it not created solely by politicians who wanted to divert resources to go to Mars?

No, it was created by the CAIB subsequent to the loss of Columbia.
 
 

As such, can it not be moved just as easily as it was created?

No, because the CAIB requires the vehicles be recertified to extend their lives beyond that date - a very expensive and difficult process.
 
That being said - another limit, currently, is contractural. NASA has only contracted for so many External Tanks, SRB refurbishments, etc... Unless Congress coughs up more money (and approves the delays in converting facilities to support Ares/Constellation - I.E. more money) it simply isn't going to happen.
 
 

It is, after all, three years away. If we can't move deadlines that far out, isn't there a chance we're overplanning, and leaving ourselves completely vulnerable to unexpected circumstances, exactly like this solar panel issue?

NASA routinely plans from 3-5 years out, to a decade or more. This is made necessary by the fact that planetary launch windows, if missed, may not recur for two years (Mars) or two _centuries_ (Pluto). Also, the hardware takes from months to years to assemble, on top of months to years of design and review effort. Training for a flight takes months. The Shuttle also has to be overhauled so often, a process taking months, so you have to plan ahead to make time available for that. Etc... Etc...

Hope they brought the duct tape...

[sgv-0027]

Of course it's going to be the really shiny "NASA" kind, but still duct tape.

Away Team extra crewman

[RealGrouchy]

He will not be electrocuted, or at least if he is, he will survive.

Of all the crewmembers aboard the ISS/Space Shuttle, Parazynski is the most experienced.

If NASA were going to kill off a character, they'd send out one of the junior redshirts to do the repair job.

- RG>

Re:D'oh!

[everphilski]

That bit about not being able to take it down for repair, well, that's going to make it into some future book on industrial design.

Pray tell, short of covering the solar array from view of the sun, how do you stop solar cells from generating electricity? It is a passive electricity generating device, not an active one (like a fuel cell or a conventional gas-powered generator). As long as it has a sufficient view factor of a light source, it generates electricity.